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Post by ChrisK on Dec 23, 2008 18:05:19 GMT -5
The power adapter doesn't have a prong for SAFETY ground as it doesn't need one. Being double insulated and galvanically isolated, a safety ground is superfluous and not required by U.L. since a single (internal) component failure will not result in a user shock hazard AND the adapter is supposed to be directly plugged into an outlet.
I would use a quality power strip and not an extension cord. If you must use an extension cord, use a quality one with a safety ground wire (three prong).
While you're at it, buy an outlet tester and test every outlet that you'll use before you use it (including any in your home).
The safety ground wire in any mains cord is not a shield for noise reduction. It shares the cord with at least one wire that has 120 VAC on it (coupling is). The proper reference place for noise shielding ground connections is the amp input.
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Post by ChrisK on Dec 23, 2008 17:31:05 GMT -5
So, are you asking for folk to come up with everything possible with two humbuckers, or specific recommendations? If it's the former, I'll quietly ignore you, but if it's the latter, clues few might help. Oh, you know, the type of music you play, the body and neck wood, the number of pots and switch in-body. I could suggest several mods which are all better because they're mine ( P-Rail). Breath baited waits he. |
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Post by ChrisK on Dec 23, 2008 17:10:17 GMT -5
Well, although we're awfully dang smart here, we're going to have some difficulty in determining exactly whose home in which this was built.  Some clues: This has "Gain", "Bass", Middle", "Treble", and "Master" so it has a preamp section with both pre and post volume controls. It has a (as in one) little transformer and, since this is a tube amp and it's near the mains cord and fuse, it's most likely a power (input) transformer. The jack labeled ".....t" is connected to the the "Gain" panel control potentiometer . This is likely the "Input". The "Master" panel control potentiometer has its wiper connected via a white wire to the jack labeled "Output". There is no output transformer. The 12AX7 is a weak sister regarding plate current compared to a 12AU7, which is sometimes used as a low power output amp stage of perhaps 1/2 watt. This is likely a preamp. It seems to have a lot of tube stages (4) for a Fender tone stack (guitar'ish) or Bauxandall structure (Hi-Fi'ish), both of which are cut-only structures, but it may also just have a cathode follower or two for tone stack drive isolation and relatively low (for a preamp) output impedance. A key to understanding this (sans schematic tracing) would be to know the resistance value of the "Master" pot. Since the controls are labeled "Gain", "Bass", Middle", "Treble", and "Master", it is likely Fender'ish in structure. www.duncanamps.com/technical/baxandall.htmlwww.duncanamps.com/technical/tonestack.htmlwww.duncanamps.com/tsc/(These are cut-only in that a passive network can only cut. While there is a gain stage before the structure as well as after the structure and the overall effect may well result in gain, since the passive structure IS NOT used as a feedback structure around a gain stage (as in that of an OP-AMP), it has the undesirable noise susceptibility of such. A Proper Active Tone Structure |
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Post by ChrisK on Dec 20, 2008 22:48:19 GMT -5
There are layered metal foil methods and conductive paint methods for guitar cavity shielding.
When one looks at the material cost, they are both similar. The labor to apply the paint seems to be much less than the foil (especially if one ensures full edge/perimeter connectivity).
Fender uses conductive paint since it can be automated.
Does anyone have experience with both, and can then recommend one over the other?
Specifically, is the foil method vastly superior to the conductive paint method?
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Post by ChrisK on Dec 20, 2008 22:40:26 GMT -5
The practice of notching feeler gauges to make nut files is interesting. You are right tho' Cyn, that the edges need to then be rounded.
However, what are you going to use for your feeler gauges when you use your notched feeler gauges to cut down to your feeler gauges used as a depth reference? (Yeah, I know, two sets of feeler gauges.)
I think that nut files are worth it since they only cut on the bottom edge. This prevents the slot sides from getting too wide.
Which led to an interesting episode at Sears a couple of years ago when I asked a female clerk where the feeler gauges were. She said "Honey, I never expected to hear that line outside of a bar".
I took a deep breath since she was quite striking and had "that look in her eye". Many thoughts went thru my mind, but since she was skilled in the use of sharp workshop instruments, I let the issue alone since it just seemed way safer.
I was actually looking for a set of feeler gauges since I couldn't find mine. I also couldn't find my set of guitar nut files. About six months ago I found both, so I now have two sets of both.
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Post by ChrisK on Dec 19, 2008 17:49:25 GMT -5
Oh, and make sure that all of the EMG pickup shields (braids) are soldered to the backs of their respective pot cases.
This is the pickup ground as well as the shield.
When you updated the design drawing at the beginning of a post, please add test such as "Edited on date".
I prefer the format CCYYMMDD, today is 20081219. This is the ONLY correct way to numerically specify a date, since it is a pre-scale factor of "clock time", and hence only a more granular reference to a point in time.
CCYYMMDDHHMMSS
In Europe they do it backwards, and in the U.S., it's inside-out. In Asia (or at least Korea), they get it.
Now, I'm not having significant success convincing the rest of the world to adopt this method (along with my file dating scheme), but then, most people a'planet are croutons anyway.
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Post by ChrisK on Dec 18, 2008 20:40:03 GMT -5
Gee Sparky, just tryin' to he£p.
It's euro back that's gonna take a "pounding" after a££.
(We don't want to see any of that "quid" pro quo either.)
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Post by ChrisK on Dec 18, 2008 20:00:42 GMT -5
Yes.
Since they all use power, they all have an output buffer in one form or another. They may have significant output impedance in the form of a weak buffer, asymmetrical drive capability (an active pull-down and a resistive pull up), or a pot on the output. If they have significant output impedance, they will be affected by what they are connected to down-chain.
A. If the question in play is "does the pedal act as a buffer when in bypass", then there may be simple ways to ascertain this.
B. If the question in play is "does the pedal have a true bypass", this can be ascertained with the meter measuring the resistance from input tip to output tip when in true bypass. If true, the resistance from tip to tip will be well under 5 Ohms. If the resistance from either tip to the ground is not infinite (or really, really large), the pedal may not have a true bypass in that it still loads the input signal even if it directly connects tip to tip.
If the resistance tip to tip is not indicative of a direct connection, then the pedal likely has a (hopefully) clean buffer function when in bypass.
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Post by ChrisK on Dec 18, 2008 19:55:34 GMT -5
Input and output are relative. The output jack on the guitar is connected to the input jack on the amp.
OK.
Uh, there's a bit more to it than this. A capacitor has capacitive reactance. This is one component of the tone circuit impedance.
Capacitive reactance is defined as 1/(2*PI*Freq*Capacitance).
PI is 3.141592654....
Freq is the particular frequency of analysis.
Capacitance is in Farads.
At 100 Hz, a 0.1 uF cap has a reactance of Xc = 15,915 Ohms.
At 1 Khz, a 0.1 uF cap has a reactance of Xc = 1,591.5 Ohms.
At 10 Khz, a 0.1 uF cap has a reactance of Xc = 159.15 Ohms.
As one can see, the reactance of a capacitor is frequency dependent, and decreases with an increase in frequency.
The tone pot has resistance. The combined impedance is the vector sum of the reactance(s) and resistance (the root of the sum of the squares).
Z = (r^2 + Xc^2)^1/2
If the pot is at 25,000 Ohms and the cap is 0.1 uF;
At 100 Hz, the impedance is = 29,636 Ohms.
At 1 Khz, the impedance is = 25,051 Ohms.
At 10 Khz, the impedance is = 25,001 Ohms.
If the pot is at 10,000 Ohms and the cap is 0.1 uF;
At 100 Hz, the impedance is = 18,796 Ohms.
At 1 Khz, the impedance is = 10,126 Ohms.
At 10 Khz, the impedance is = 10,001 Ohms.
If the pot is at 2,000 Ohms and the cap is 0.1 uF;
At 100 Hz, the impedance is = 16,041 Ohms.
At 1 Khz, the impedance is = 2,556 Ohms.
At 10 Khz, the impedance is = 2,006 Ohms.
As one can see, the overall impedance varies with the setting of the tone pot, with the higher frequencies having a lower impedance than the low frequencies.
Now, the tone circuit is in parallel (across) with the output signal and ground. As a result, it shunts the output signal to ground by forming a frequency-dependent AC voltage divider comprised of the tone pot reactive components across the output and the pickup reactive components which, in this active pickup case have an output impedance (mostly resistance) of 10,000 Ohms, in series with the output.
In essence. it (increasingly) attenuates the output signal level as a function of increasing frequency.
If the tone circuit was in series with the output signal, it would cut the low frequencies.
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Post by ChrisK on Dec 18, 2008 19:01:54 GMT -5
So how much does £500 weigh?  ;D ;D |
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Post by ChrisK on Dec 18, 2008 18:55:28 GMT -5
Because this often has more to do with how it "feels" great.
(This gets lost in translation.)
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Post by ChrisK on Dec 18, 2008 18:48:30 GMT -5
A buffer is an amplifier. It usually does not (significantly) increase the signal voltage level, but it does increase the signal drive current level. This occurs due the buffer having a much lower output impedance, and a much higher current drive capability than the unamplified passive guitar pickup signal.
Think of it as power steering or power brakes. The steering wheel or brake pedal doesn't move any further than the unbuffered mechanical systems of yester-year (I don't oft have opportunity to use "yester-year" in a sentence, let alone "yester-millennia", so bear with me please), but they are much easier to operate and do easily overcome the mechanical resistance (impedance) of the steering and brake linkages.
In essence, the buffer is a bull(y), less than concerned or effected by the sundry ceramics (capacitance) encountered on its way thru the China shop.
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Post by ChrisK on Dec 18, 2008 18:31:59 GMT -5
tedfixx!Most excellent! You "see" things well. Rather than engage in more word-smithing, I'm posting a slightly edited version of your drawing. It will clarify that whole unfortunate output jack conundrum. I added some "direction" on how the lever switch needs to be oriented. I also added a connection between the pot cases (I never rely on the cavity or pickguard shield for this, it's NOT a conductor, it's a shield). Again, most excellent! Stick around, we need you. 
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Post by ChrisK on Dec 17, 2008 20:55:10 GMT -5
One still might want to use a 500K pot tho'.
You can eliminate the mini-toggle switch with a push pull pot for cap selection.
And, if a SPDT Center-OFF switch is used, one can get three cap values, 0.047 for one, 0.022 for the other , and 0.015 (the "woman tone") for the third (series rules) with just two caps.
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Post by ChrisK on Dec 17, 2008 20:44:46 GMT -5
No, it is a DP3T shorting (make before break) lever switch with two extra notches in the shorting positions. While it has 5 distinct positions, it is not a DP5T switch. It is exactly the same switch electrically as a Tele DP3T lever switch. Which is not correct since you want something that everyone else doesn't want everywhere else. This might help on switches. Electronics Templateswww.alloutput.com/Wiring/5way.htmlYou need to re-read my first post where I describe how to do this design, first with both volume pots always in the circuit, and second with each volume pot in circuit only if the connected pickups are selected (you need to choose which one that you want - I suggest door number 2). Once you understand the switch, you can "see" what I say. One pole (side) of the lever switch will be used to select which pickup (neck and/or middle) will go to the neck/middle volume pot wiper. The bridge pickup is always connected to the wiper of the bridge volume pot. The other pole will select which volume pot hot terminal is selected and connected to the output jack "tip" and to the master tone pot circuit. On my drawings of lever switches, "P" denotes the pole terminal for each section/side. I'm doing things this way to determine what you can "see". I could just draw a diagram, but my time isn't free, and costs the poster their full attention. Your stereo jack diagram is incorrect. The EMG one has "T", "R", and "S" which stand for "tip, ring. and sleeve" (your black wires are reversed). The "tip" is the signal output like all other guitars. The "sleeve" is the signal ground like all other guitars....... |
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Post by ChrisK on Dec 17, 2008 20:19:10 GMT -5
Just don't get too carried away....   |
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Post by ChrisK on Dec 16, 2008 23:19:42 GMT -5
Yes.  With the recession (er, boomer speed bump), them redwood stained pine picnic tables and benches just ain't sellin' as well..... |
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Post by ChrisK on Dec 16, 2008 23:13:41 GMT -5
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Post by ChrisK on Dec 16, 2008 23:07:01 GMT -5
Since you want to share one volume pot between the neck and middle pickups, one pole (section) of the 5-way switch will have to select the neck/neck+middle/middle/middle+none/none for the white leads from the neck and middle pickups to the wiper of their volume pot.
The other pole (section) of the 5-way switch will have to select the none/none+none/none/bridge+none/bridge for the white lead from the bridge pickup to the wiper of its volume pot.
The hot terminals of both volume pots will be connected together, to the master tone circuit, and to the tip terminal of the output jack.
Conversely, to avoid having both volume pots always in circuit, the first pole can select the neck/neck+middle/middle/middle+none/none for the white leads from the neck and middle pickups to the wiper of their volume pot as before.
The bridge pickup can be connected to the wiper on the bridge volume pot,
The other pole of the 5-way switch can select the NMVolPotHot/NMVolPotHot/NMVolPotHot/NMVolPotHot+BVolPotHot/BVolPotHot for the output to the master tone circuit, and to the tip terminal of the output jack.
The shields of each pickup should be connected to their respective volume pot back shells, and all to circuit ground.
The red wires of course come from the battery (+).
Your drawing of the 5-way switch and output jack lack specific detail or meaning. The switch has two sections. The output jack will have a tip, ring, and sleeve connection,
Your drawing of the bridge volume pot has the two end terminals reversed (circuit ground and hot).
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Post by ChrisK on Dec 16, 2008 22:40:33 GMT -5
At a minimum we will need well-focused pictures of the wiring that you have implemented.
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Post by ChrisK on Dec 16, 2008 20:08:38 GMT -5
Uh,
No.
He's offering the unwary a chance to buy degrees in "acousti-phonics, bionics and hydroponic intelligence". He can offer these at such an attractive price since he has a "box of them".
Clue #1. Acousti-phonic is not a real word. If it was, it would be redundant.
Clue #2. Bionics - see the 6 Million Dollar Man.
Clue #3. No matter what they tell you, plants just ain't gonna ever be that smart.
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Post by ChrisK on Dec 15, 2008 23:34:57 GMT -5
Well, no. Pine was used in the original Esquire. It has its place (and tone). Fortunately pine has been replaced by spruce. |
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Post by ChrisK on Dec 15, 2008 23:24:43 GMT -5
I believe that as we age, we need a thicker-backed neck to avoid hand fatigue.
On the guitars that I build, I use either a 1 7/8" boat neck or a 1 3/4" fatback neck. Both of these are a full 1" thick with the boat being a soft "V" and the fatback being a "U".
Another advantage is that a 1" thick neck significantly increases both the tone and sustain (uh, physics).
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Post by ChrisK on Dec 15, 2008 23:15:39 GMT -5
That depends on whether you care about money. 70's Strats in reasonable condition are going for up to a couple/few thousand dollars today. If you refinish it, it will be devalued. The 70's also were not known as the pinnacle of Fender build quality. There are several books that list the values of guitars. If you live near a library, such as those run by "Borders" and "Barnes&Noble", you could easily ascertain its value. I'd be sure first.  P.S. If you're not located in the U.S., maybe one of us could check out the book value the next time that we're in such a library. |
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Post by ChrisK on Dec 15, 2008 22:59:55 GMT -5
Impedance and resistance are not the same except for purely DC circuits with steady-state signals.
Resistance, along with inductive and capacitive reactance, are the components that make up impedance. Therefore, resistance is only one of the three components of impedance.
If you still have that physics book, check back in (to it).
A piezo pickup is primarily capacitive, with a relatively strong voltage signal output with a significantly weak current output. In essence, they have a very high output impedance.
A passive magnetic pickup in comparison has a relatively low output impedance comprised of the resistance of the coil, the inductive reactance of the coil, and the inter-winding capacitance of the coil. These components are not simply added together, but are combined in a vector sum/phasor relationship. It's called AC circuit theory.
The fact that piezo pickups have a high output impedance requires that they are loaded as little as possible (the multi-meg Ohm pot) and usually require a buffer. Since a piezo is unable to adequately drive the load of a lower value pot, it's also unable to adequately drive a guitar cable where the capacitance will attenuate the high frequencies and the relatively low guitar amp input impedance will significantly attenuate the overall signal.
Also, a guitar amp is unable to adequately process and amplify a piezo signal.
I have several guitars with piezo pickups. In all cases they have an active pre-amp inside the guitar and use acoustic guitar amplifiers, PA systems, or hexaphonic modelers. I have never considered the use of a passive piezo pickup.
Are you sure that you don't want to try to figure out what went wrong with the pre-amp? (We'll help.)
No, it's a treble bypass cap to enhance the high frequencies lost when the volume pot is turned down.
In no useful way.
This appears to be a circuit used on the output of the pre-amp to effect volume and tone controls with the same relative impedance of single coil magnetic pickups.
If you combine a 5 Meg piezo pot with a 250K passive pickup pot, the 250k pot will significantly attenuate the piezo signal when both are selected.
If you run the signals separately (tip/ring) as shown in the Graphtech manual, you still have to deal with the cable capacitance and amplifier input impedance.
I do know where to get pots like this (in the U.S.), but would strongly recommend against it.
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Post by ChrisK on Dec 15, 2008 22:35:36 GMT -5
There is no specificity given for this cable, other than the connectors are "sturdy" and that the cable is "professional grade". It may be a fine cable or it may not. This is completely indeterminate from the lack of specificity. Typically one would want to know the capacitance of the total cable or per foot, and the shielding effectively. Due to the low cost, and the freedom from statements about "oxygen free copper", "disingenuous ethereal spatial reasoning/seasoning", and "free range baba ghanoush", at least you're not being conned. Let us know how it sounds. |
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Post by ChrisK on Dec 14, 2008 0:07:33 GMT -5
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Post by ChrisK on Dec 13, 2008 23:44:51 GMT -5
Yes, and they have an unnatural fear of spiders (Boris sez).
I'd stick with a rails style just to get even magnetic coverage. You do get to choose series or parallel for the dual rails pickups.
You could first try a 6 pole Strat pickup, it might be ok.
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Post by ChrisK on Dec 12, 2008 21:41:53 GMT -5
No, it just means that I'm not (still) p  d-off enough to go thru the trouble of editing the pics and reposting them. I looked on their site recently and did not see the name of the moron that went out of his way to incur my ire. I'll send an email to see if he's still there. I still take great umbrage at Warmoth's total ignorance of my email to Ken Warmoth about this. It's obvious that they don't give a shite about customer issues. And, their prices have gone completely out of sight (thru the roof). |
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Post by ChrisK on Dec 12, 2008 21:35:59 GMT -5
And before you get too infatuated with building one, My "Proper" Telecopy indicates at the bottom of the thread that the cost for a finished body and neck plus upscale components cost $1,000 two years ago. The PadoukCaster ran about $800, but it required no finish on neither the body nor the neck. Only at the American (U.S.) level and above does building compare with store-bought. You get exactly what you want, but the resale is less than the mundane Fender offerings unless you find a lustful buyer. |
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;D ;D
